Question: Combination of Access and Constraining

[papand0pul0@yahoo.com (Papandopulo)]

Small Ada question:

I need one function to accept
an array of unknown size of Boolean,
so I declare type and function:

type Tp is array (Positive range <>) of Boolean;
type Tp_Access is access all Tp;

function Fn (Arg : in Tp_Access) return Natural;

Now I try to call it with the constrained array:

declare
  type TpCon is new Tp(1..1);
  Arr : aliased TpCon;
begin
  Arr(1) := True;
  Res := Fn (Arr'Access);
end;

Compiler says on the invocation line:
expected type: Tp_Access defined at ...
found type TpCon defined at ...

I think that access to constrained
type should be convertible to access
to unconstrained type.

So where I am going wrong here ?

Thanx,
George